Portable calibration system

ABSTRACT

A portable shippable automated calibration system for high torque power tools is disclosed. The system includes a self-contained highly durable and shippable container that may comprise a power source, central processor, visual user interface, mechanical interface for coupling with power tools to be calibrated, communications systems for communicating with a power tool being calibrated and/or with on-site or cloud based data systems. The system may be delivered to sites desiring on-site power tool calibration, tools are calibrated and updated calibration factors are automatically uploaded into the calibrated tool and a calibration certificate is published with the particulars of the calibration completion.

FIELD OF THE DISCLOSURE

The present disclosure relates to the field of power tool calibration,particularly to systems and methods to provide efficient andcost-effective calibration of high torque power tools at distributed orremote sites.

BACKGROUND

The use of high torque assembly tools is an important part ofmanufacturing and other fastening processes. The manufacture or assemblyof many devices requires application of pre-determined and specificallyengineered torque loads to the fasteners of the devices. Fastening atdesigned torque levels is essential not only for reliability of thefastening but also for safety in many devices. It is well known thathigh torque assembly tools used in such applications require regularcalibration to ensure that the tools deliver the pre-determined torqueloads to the fasteners on which they are used.

The process of calibrating assembly tools, particularly high torqueassembly tools, is complicated. Many tool owners rely on a third-partycalibration specialists to perform this service on their tools. Sincehigh torque assembly tools require regular calibration, many tool ownersmust expend significant budgets to either pay third-party calibrationspecialists to perform the calibration service or to buy expensivecalibration equipment and train themselves to calibrate their own hightorque assembly tools. Cost effective and regular assembly toolcalibration is further hindered by the fact that many high torqueassembly tools are used at sites—such as on pipelines, windfarms, orremote construction sites—remote from third party calibration sites andin some instances remote from any substantial tool service sites.

Therefore, there is a need for a reliable, efficient, and cost-effectivecalibration system for high torque tools that can be used in remotesites without the need of third-party calibration services and alsowithout the need of advanced training for self-calibrating tool owners.

SUMMARY

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

The present disclosure relates to a portable, shippable calibrationsystem for power tools, including particularly, high torque power tools.The system may comprise unique electrical and mechanical components andsystems in a robust shipping case which is easily transportable andshippable but also protects the hardware during shipping. Embodiments ofthe system can be shipped to virtually any customer site needingcalibration updates on their power impact tools. For example, in someinstances, a supply site, whether local or centralized, of portable,shippable calibration systems can be maintained and power tool usersdesiring calibration of their tools can simply request shipment anddelivery of the portable and shippable calibration system from thesupply site. When the shippable calibration system is received, the usercan, with the automatic features of the present system, conduct her/hisown calibration on the power tools and self-certify the calibration.After the calibration, the shippable calibration system can be shippedback to the local or centralized supply or shipped directly to anothertool owner who has also requested shipment and delivery of thecalibration system. Using this system, a power tool user need notpurchase her/his own calibration equipment, but can simply requestshipment of the present calibration system and use the system'sautomated controls to calibrate and certify power tools on site at thetool user's scheduling convenience. Accordingly, the present disclosureprovides a simple, easy-to-use, mobile high torque power toolcalibration system.

With this system a power tool user can avoid the disadvantages ofprevious systems which may require periodically shipping each power toolto a regional lab for calibration and certification, which would requirethe user maintain redundant tools to be used while other tools are sentoff for calibration. Other disadvantageous previous calibration optionsincluded scheduling and paying for a calibration services vendor totravel to the user's tool, assembly, or work site so that the thirdparty calibration services vendor could conduct the necessary toolcalibration using the service company's equipment which typicallyrequired trained and certified calibration technicians. Again, thesethird party calibration services were subject to the third party'sscheduling and work requirements. Lastly, a tool owner or user couldpurchase her/his own calibration system, which systems are typicallylarge and complicated, and then conduct and maintain training andcertification of her/his own employees to conduct calibration using thepurchased calibration system. But even this last option does not answerthe needs of many assembly and fastening operations that are conductedaway from even the user's calibration labs such as fastening operationalong pipelines crossing the country or at remote wind farms or otherconstruction or assembly sites.

With the present system a tool user can self-certify her/his high torquepower tool calibrations at her/his own scheduling convenience and at anylocation. Thus, the tool user avoids the numerous disadvantages andexpenses of the prior calibration system 10 requirements.

The present shippable calibration system may be self-contained andinclude everything necessary to conduct calibration operations on evenvery sophisticated high torque power tools. Further, the present systemmay comprise control systems that automate much of the calibrationprocess and lead the operator through the calibration process so that ahigh level of calibration training or certification is not required toself-certify the calibration of the tools. Further, a controlledenvironment, such as a laboratory or tool shed, is not required forcalibrations according to the present system thus facilitatingcalibration at virtually any remote work site such as a pipeline orwindfarm. The self-contained and highly portable aspects of the presentsystem also provide clear advantages in an assembly plant environment.With the present system calibration procedures can be conducted at timesalong the assembly line or process that do not interrupt normal assemblyoperations and that do not require removal of the tools from the “floor”of the assembly line or other assembly site as the portable calibrationsystem may be brought directly to the tool location at the assembly lineor assembly site.

The robust shipping case may include everything needed to perform atorque calibration of a high torque, precision assembly tool. The systemmay comprise hardware such as torque transducers, appropriate sizingcouplings, controller with signal processor display, mechanical toolinterface, electrical tool interface cable and wireless connectivitydevices, communications capabilities to conduct data transfer with theparticular tool being calibrated to identify the tool and its particulardesign characteristics, tool settings and other data that may be held bythe tool. Additionally, the system has communications capabilities tocommunicate to local or on-site data (such as an assembly plant's datasystems) or to communication via wireless or cellular protocols toremote storage such as the “cloud”.

A first aspect is directed to a portable high torque power tool torquecalibration system, comprising: a portable shippable container in whichare mounted a mechanical tool interface, a user interface and centralprocessor unit; the mechanical interface couplable to a high torquepower tool to be calibrated and configured such that the mechanicalinterface simultaneously locks the power tool against spinning andreceives torque output from an output spindle of the power tool; themechanical interface further comprising a torque transducer operativelyconnected to the central processor; the central processor configured toprocess signals received from the torque transducer and calculate andupload to the power tool being calibrated a calibration correctionfactor specific to the power tool being calibrated.

In another aspect, the system further comprises: an electronic dataphysical connection port mounted to the calibration system andconfigured to be connected via data cable to an electronic data physicalconnection port of a power tool being calibrated; and wherein thecentral processor is configured to download specific tool identificationinformation from a power tool being calibrated via the electronic dataphysical connection port.

In another aspect, the central processor is configured to upload atleast one calibration correction factor to a power tool beingcalibrated, such calibration correction factor being specific to theparticular power tool and a targeted output torque of the power tool.

In another aspect, the mechanical interface comprises both a femalereaction collar coupling and a square spindle female coupling jointlymounted to simultaneously couple with a male reaction collar and a malesquare output spindle of a power tool.

In another aspect, the central processor is configured to receive atarget torque setting from a power tool being calibrated, to processsignals from the torque transducer and to calculate a calibrationcorrection factor based on the signals and the target torque andspecifics of the power tool, and to upload the calculated calibrationfactor to the power tool.

In another aspect, the central processor, based on data downloaded fromthe power tool being calibrated, is configured to identify anappropriate calibration process for the particular power tool beingcalibrated; and is further configured to activate a trigger actuatorcoupled to a trigger of the power tool, to identify when the toolcontrol unit determines that the tool has reached its target torqueoutput, to process signals received from the torque transducer todetermine the actual torque received at the mechanical interface fromthe power tool operating at its target torque output, to compare theactual torque with the target torque, to compute a new calibrationcorrection factor for the power tool at [at that target torque output],and to upload the new calibration correction factor to the data memoryunit of the power tool.

In another aspect, the calibration system further comprising a top plateto which the female reaction collar coupling is mounted and againstwhich the torque transducer is arrested.

In another aspect, the female square spindle coupling has an axisthrough the center of the coupling and the coupling is configured in aspindle receiving body partially rotatable about the axis of the femalesquare spindle coupling.

In another aspect, the spindle receiving body is mounted on at least onebearing and is at least partially rotatable about the axis of the femalesquare spindle coupling.

In another aspect, the body further comprises a torque transducerpositioned to at least partially rotate about the axis of the femalesquare spindle and is also arrested against rotation by at least onearresting block mounted to the plate.

In another aspect, the system is configured such that a power tool canbe coupled to the female reaction collar coupling and the female outputspindle coupling, the power tool power source activated, the power toolproviding a target torque output to the female square coupling that ismeasured by the torque transducer.

Another aspect is directed to a method of providing distributedself-certification of high torque power tools by tool operators, themethod comprising: providing at a supply site a portable self-containedcalibration system comprising a shippable durable container in which ismounted an automated high torque power tool calibration system;receiving a request from a tool operator at a location remote from thesupply site for shipment of the calibration system shipping thecalibration system to the tool operator at the remote location;receiving the calibration system at the remote location; connecting apower tool to be calibrated to the automatic calibration system;calibrating the power tool using the automated calibration system;storing a torque calibration certificate issued by the calibrationsystem; and returning the calibration system to the supply site.

In another aspect, the step of connecting a power tool to be calibratedto the automatic calibration system further comprises connecting a datacommunications cable from the calibration system to the power tool andcoupling the power tool to a mechanical interface of the calibrationsystem such that the mechanical interface simultaneously locks the powertool against spinning and receives torque output from an output spindleof the power tool.

In another aspect, the step of calibrating the power tool using theautomated calibration system further comprises downloading tool specificidentifying information from the power tool to the calibration systemover the connected data communications cable; the calibration systemdetermining a recommended calibration protocol for the specific powertool based in part on the downloaded tool specific identifyinginformation; the calibration system identifying a target torque settingof the power tool from data downloaded from the power tool; thecalibration system activating a trigger actuator coupled to the powertool; the power tool motor providing torque to the output spindle of thepower tool until an electronic control system of the power tooldetermines that the power tool target torque output has been achieved;the torque from the power tool output spindle being transferred to acalibration system torque transducer; signals from the calibrationsystem torque transducer being monitored by a central processor duringthe period of the power tool providing torque output to the calibrationsystem; the central processor processing the signals from the torquetransducer to determine the actual torque output received from the powertool at the calibration system and comparing the actual torque to thepower tool target torque; the central processor calculating a correctionfactor to be applied by the power tool to bring the power tool actualtorque output into acceptable correlation with the target torque of thepower tool; the calibration system uploading the calculated correctionfactor to the power tool electronic control system; the calibrationsystem uploading a calibration certificate verifying the completedcalibration of the power tool.

In another aspect, the calibration system uploads a calibrationcertificate relating to the power tool to data records accessed via thecloud by way of a cellular data system embodied in the calibrationsystem.

In another aspect, the calibration system checks the power tool firmwareand determines if a power tool firmware update is recommended and, atthe option of the tool operator, uploads updated firmware to the powertool.

In another aspect, the calibration system accesses data records via thecloud to help determine whether a firmware update for the power tool isrecommended and to download a recommended firmware update.

In another aspect, the calibration system performs the calibration usingself contained battery power without accessing an external power source.

Another aspect is directed to a portable high torque power tool torquecalibration system, comprising: a portable shippable container in whichare mounted a mechanical tool interface, a user interface and centralprocessor unit; the mechanical interface couplable to a high torquepower tool to be calibrated and configured such that the mechanicalinterface simultaneously locks the power tool against spinning andreceives torque output from an output spindle of the power tool; themechanical interface further comprising a torque transducer operativelyconnected to the central processor; the central processor configured toprocess signals received from the torque transducer and calculate andupload to the power tool being calibrated a calibration correctionfactor specific to the power tool being calibrated; and the calibrationsystem configured to automatically conduct the calibration of a hightorque power tool using only power from a self-contained battery systemin the calibration system and without the use of an external powersupply.

Additional novel and advantageous aspects of various embodiments of thepresent disclosure will be apparent to one of ordinary skill in the artin view of the drawings and the detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate implementations of the conceptsconveyed in the present disclosure. Features of the illustratedimplementations can be more readily understood by reference to thefollowing description taken in conjunction with the accompanyingdrawings.

FIG. 1 illustrates an example of a portable shippable calibration systemaccording to certain embodiments of the present disclosure.

FIG. 2 illustrates a schematic of certain components of some embodimentsof the present disclosure.

FIG. 3 illustrates an example representation of a high torque power toolthat may be calibrated in accordance with the present disclosure.

FIG. 4 illustrates an exemplary non-portable and non-shippablecalibration system.

FIG. 5 illustrates a high torque power tool without a reaction armattached.

FIG. 6 illustrates a schematic view of a strain gauge based torquetransducer that may be used in some embodiments of the presentdisclosure.

FIG. 7 illustrates a schematic cross-sectional view of a mechanical toolinterface according to certain embodiments of the present disclosure.

FIG. 8 illustrates a schematic cross-sectional view of a mechanical toolinterface juxtaposed with a power tool output according to certainembodiments of the present disclosure.

FIG. 9 illustrates a schematic cross-sectional view of the mechanicaltool interface of FIG. 8 with the power tool output coupled to themechanical tool interface.

FIG. 10 is a process flow chart of a shippable calibration system supplyprocess.

FIGS. 11A-E illustrate exemplary process flow charts of a calibrationprocess according to certain embodiments.

FIGS. 12A-12C illustrate exemplary adapters for different sized powertools and the portable calibration system.

FIGS. 13A-13C illustrate exemplary cascading load cells as may beincluded in the portable calibration system.

FIG. 14 shows an exemplary plot of output signal vs applied load forcascading load cells.

DETAILED DESCRIPTION

The portable and shippable calibration system 10 of the presentdisclosure may be used with high torque power tools such as discussed inconjunction with FIGS. 3 and 5 and provides a much improved andefficient calibration system 10 than is provided in traditional hightorque power tool calibration systems such as discussed in conjunctionwith FIG. 4.

An exemplary mechanical layout of an embodiment of a portable andshippable calibration system 10 according to the present disclosure isshown in FIG. 1 and a schematic of corresponding electrical componentsof an embodiment of the calibration system 10 is shown in FIG. 2.

FIG. 1 shows a mechanical layout representation of an example of aportable shippable power tool calibration system 10 according to certainembodiments of the present disclosure. Shown is a durable, portable andshippable case 12 which may comprise a cushioned interior 14 and inwhich may be mounted a user interface 16 which is operatively coupled toa central processor 18 (shown in FIG. 2) also mounted in the shippablecase 12, a battery or other power supply compartment 20, a mechanicaltool interface 22, a detachable USB connector 24, and a detachable powercord 26. The calibration system 10 may be entirely self-contained withinthe durable shippable case 12.

FIG. 2 shows a schematic electrical layout of an embodiment of aportable shippable power tool torque calibration system 10 according tothe present disclosure and shows additional components, capabilities andfeatures of the embodiment of FIG. 1. The central processor 18, whichmay also comprise data memory and operating system data storage, may besecurely mounted in the shippable case 12 and operatively connected tothe user interface 16 which may comprise an LCD and various user inputfeatures such as buttons for alpha-numeric input to the processor andnavigation buttons. In some embodiments the user interface 16 may alsoinclude a touch screen and in some embodiments may entirely comprise atouch screen interface. Also operatively connected to the centralprocessor 18 may be a port 32 for a data storage device, which in someembodiments may comprise removable data storage devices 30 such as an SDcard.

The central processor 18 is also operatively coupled to a transducer 34so as to receive transducer 34 output signals related to the value ofthe torque or stress applied to the transducer 34 by the power tool 70during power tool calibration. The central processor 18 operatingprograms calculate the torque applied to the transducer 34 based on thetransducer 34 output signals and previous calibration of the of thetransducer 34 in the calibration system 10.

The calibration system 10 may also comprise system-to-tool communicationcapability to communicate between the calibration system 10 (includingwith the central processor 18) and a power tool 70B (or 70 of FIG. 3)being calibrated. FIG. 2 shows an example of such a system-to-toolcommunication system, showing USB port 36 operatively coupled to thecentral processor 18. USB cable 38 is coupled to USB port 36 and isoperatively coupled to a USB port (not shown) in the exemplary powertool 70B. The system-to-tool communications system may be a physical(wired) system (such as USB) of any protocol. The system-to-toolcommunications system may also comprise a wireless link such asBluetooth or other wireless protocol communications link.

The calibration system 10 may also comprise system-to-facilitiescommunications capabilities which may communicate with facilities wherethe calibration system 10 is being used to calibrate power tools orresources accessed via the cloud. Such system-to-facilitiescommunications links may include WIFI 33 or any other acceptableprotocol including, for example, internet, FieldNet, Ethernet or otherprotocols. Further the system-to-facilities communications capabilitiesmay comprise cellular communications capabilities 31 which maycommunicate with systems and data records on the cloud. Via thesystem-to-communications systems the calibration system 10 cancommunicate data to and from power tool user facility computer and datasystems and data storage and also with the internet and cloud datastorage.

The calibration system 10 may also comprise Global Positioning System(GPS) capabilities 28 so that the geolocation of each tool at the timeof calibration (as well as the location of the calibration operations)can be automatically and accurately established. The GPS capability orunit may be operatively coupled to the central processor 18 to provideappropriate location data to the central processor 18.

The calibration system 10 also comprises updatable programmed systems tostart up and operate the calibration system 10, guide a user through thesteps of calibrating one or more power tools, access and store data oneach power tool 70B (or 70), and access on-site, cloud or otherdatabases to download from data archives data relating to the powertools and upload data regarding the power tools (including data relatingto the calibration of the power tool 70B (or 70)). Further, thecalibration system may also update any power tool 70 firmware or othersoftware.

Accordingly, the present calibration system 10 can provide wired,wireless, cellular or other connectivity to data records to access allservice records for a power tool 70 being calibrated, create an archiveor cloud a record for each tool of where calibrated, what tool wascalibrated, date of calibration, and/or calibration results. The systemamong other things can call down data from the archive, use power toolbirth certificate, and update calibration data for any calibrated tool.

The calibration system 10 may also comprise an adaptable power supply 35to be used with a variety of power tools being calibrated and which maybe configured to automatically adjust voltage and amperage supply tosubstitute for a power tool battery 80 (shown in FIG. 3) (so that localcalibration operations using the present calibration system 10 will notbe held up by lack of an available charged battery).

The calibration system 10 may also comprise a tool trigger actuator 39in operative communication with the central processor 18. The tooltrigger actuator 39 may comprise a solenoid trigger actuator that asoperated by the central processor 18 can control the trigger actuationof a power tool 70 being calibrated to accomplish full trigger poweractuation and appropriate start and end of trigger actuation insynchronization with the appropriate stages in the calibration process.The tool trigger actuator 39 may serve to reduce human or operator errorin the calibration processes accomplished using the present calibrationsystem 10.

The calibration system 10 may also comprise a battery 29 that serves topower the calibration system 10 to accomplish calibration processes evenwithout availability of an AC electric power supply at the calibrationsite, such as at a remote assembly or construction site or at otherlocations on an assembly site with limited access to AC power.Furthermore, the calibration system 10 may comprise an AC electric powerconnection 26 and/or transformer to utilize local AC power to operatethe calibration system 10 and/or to recharge the calibration system 10battery 29.

FIG. 3 illustrates an example of a high torque power tool 70 that may becalibrated in accordance with the present disclosure. FIG. 1 shows anelectrically powered high torque power tool 70 comprising a grip 72, anactivating trigger 74, a torque multiplier 76, an output spindle 78, anda battery 80. The power tool 70 may also comprise an operator handle 82that may be adjustable for user comfort and flexibility. The power tool70 may also comprise a reversing switch (not shown) and may utilize abrushless motor 84 which supplies rotational energy to the outputspindle. The output spindle may be a conventional male power tool outputfitting having a square cross-sectional shape, although othercross-sectional shapes, such as a spline, may also be used. Varioussizes of output fitting, such as ¾ inch and/or 1 inch, may also beprovided in exemplary power tools. Further, the power tool 70 maycomprise a control unit 86 and memory 88 to control and track theoperations of the tool. Typical high torque power tools may provide,depending on a particular model design, torque outputs ranging fromabout 200 Nm to as high as 4000 or more Nm and output spindle rpm offrom about 4 rpm to as high as 110 or greater rpm from a motor speed oftypically about 20,000 rpm.

The power tool 70 may also comprise electronic control systems 90, whichmay comprise a tool control unit 86 and tool data memory unit 88, andwhich manages operation of the power tool 70 under the control of thetool operator. The power tool 70 electronic control systems 90 may beoperatively coupled to the trigger 74 and other user controllableswitches or input devices and a multi-function display and user inputmodule 91. The power tool 70 electronic control systems 90 may furtherbe operatively coupled to the battery 80 and the electric motor 84 aswell as an internal (to the power tool 70) torque transducer 94 whichmeasures torque output at or from the output spindle 78. The torquetransducer 94 at the output spindle 78 and the tool control systems 90may provide closed-loop transducer control with the transducer 94 todeliver precise torque and accurate, traceable results in the power tool70 torqueing operations. Using calibration factors stored in theelectronic control systems 90, such as in power tool 70 data memory 88,the electronic control systems 90 can monitor the torque output from theoutput spindle 78 when the power tool 70 is in operation to ensure thatan intended torque (the “target torque”) is applied to a particularfastener being torqued by the power tool 70. The target torque may beinput or changed via the user input module 91.

The power tool 70 may also comprise communications systems, devices orports, such as cellular communications, Bluetooth, wireless, Ethernet,Fieldbus, USB or other protocols for convenient programming of the tool,data transfer to and from the power tool 70, and/or other processcontrol.

The power tool 70 of FIG. 3 also comprises a torque multiplier 76, whichin the illustrated embodiment comprises a gearbox. The torque multiplier76 receives rotational energy from the motor 79 and employs an epicyclicgear train having one or more stages to produce a higher torque (andlower rotational speed) at the output spindle of the torque multiplier76 than was received from the motor 79. Each stage of gearing in thetorque multiplier 76 multiplies the torque produced at the outputspindle 78. Torque multipliers can be designed to produce a range oftorque and rpm outputs depending on the intended use of the power tool70 and the characteristics of the power tool 70 motor 79. The torquemultiplier 76 also comprises a reaction collar 92 which in typicalfastening operations is coupled to a reaction arm 94 which braces thepower tool 70 against counter-rotation in reaction to the torque appliedby the power tool 70 on the fastener during fastener operations. Thereaction arm 94 can be of varied designs to accommodate use of the powertool 70 in particular fastening operations and to various devices towhich the fasteners are being driven.

FIG. 4 shows an exemplary non-portable and non-shippable power tooltorque calibration system. Shown in FIG. 4 is a calibration technician102 standing at a typically large calibration unit 104 in the process ofcalibrating a power tool 70A. As shown in FIG. 4 the power tool 70A iscoupled to a joint simulator 106 which is in turn coupled to andrestricted by a large hydraulic pneumatic brake. A reaction arm 94A issecured by a reaction arm brace 110. Systems such as that shown in FIG.4 are typically operated by highly trained technicians employed bycalibration operators who own the calibration systems. Generally, suchcalibration systems are located in calibration labs geographicallydispersed to serve the needs of tool users. In such cases, tools needingcalibration are shipped to the calibration labs for calibration thuslimiting the use of the tools for the user while the tools are beingtransported to and calibrated at the geographically dispersedcalibration labs. In some cases the large calibration units such asshown in FIG. 4 can be mounted in service trailers that are towed toremote power tool user sites and there operated by the calibrationtechnicians of the calibration labs.

FIG. 5 shows an exemplary high torque power tool 70 such as may becalibrated using the portable calibration system 10 disclosed herein.Shown is the square male output spindle 78 of the power tool 70, thetorque multiplier 76 gearbox, the splined reaction collar 92 (with noreaction arm attached to the reaction collar 92) and the handle 72. Incertain embodiments of the present disclosure any reaction arms attachedto the reaction collar 92 are removed prior to calibration to fullyexpose the reaction collar 92 for coupling to the mechanical interfaceof the calibration system 10. It is also noted that in FIG. 5 no battery80 is shown attached to the power tool 70. A battery 80 or other powersource (such as the adaptable power supply 35 described above) should becoupled to the power tool 70 during calibration since operation of themotor is a necessary part of the calibration operation.

In the calibration process of the present calibration system 10, thepower tool 70 to be calibrated couples with the portable calibrationsystem 10 via the mechanical tool interface 22 and simultaneouslyoperatively couples to the strain gauge based torque transducer 34 as isschematically shown in FIGS. 6-8. As also shown in FIGS. 6-8, the squaremale output 78 of the power tool 70 can be received in a female squarereceiver or coupling 40 positioned in a spindle receiving body 42 of thetransducer 34. As will be described below, the body 42 of the transducer34 is mounted in the portable calibration system 10 in such a fashionthat it can rotate, to some degree, about an axis 44 of the femalesquare receiver or coupling 40. Rotation of the transducer 34 about theaxis 44 of the female square receiver 40 however is arrested byarresting blocks 46 interacting with extension 85 of the body 42. Duringcalibration operations, the electric motor of the power tool 70 isactivated (such as by solenoid trigger actuator), rotational energy istransferred into the multiplier gearbox (torque multiplier 76), and ahigh torque rotational output is transferred from the male square output78 to the female square receiver 40 of the transducer 34. Whereas thehigh torque rotational output transferred to the female square receiver40 acts to rotate or torque the transducer 34 about the axis 44 of thefemale square receiver 40, such rotation is arrested by arresting blocks46 and a torque force is applied along an axis 47 of extension 45 of thetransducer 34. As torque (stress) is applied to the strain gauge asignal is output to the central processor 18 reflective of the value ofthe stress applied to the strain gauge by the power tool 70 during powertool calibration.

In some embodiments, arresting blocks 46 are spaced to permit somerotational motion by extension 45 about axis 44 before extension 45 isfinally arrested by one of arresting blocks 46. In various embodiments,a space 49 between arresting blocks 46 and extension 45 may be ofvarying dimensions permitting predetermined rotational movement ofextension 45. Further, an angle encoder 43 may be positioned, such as ona top plate 48 (shown in FIG. 7) to measure the rotational displacementor angle displacement of extension 45 or body 42. The angle encoder 43may be applied in calibration operations which allow for or include some“lost motion” as the transducer rotates either forwards or backwardsthrough the spaces 45 and while the angle encoder 43 measures therotational movement. Certain precision assembly tools have angleencoders to aid in the fastening process and permit more sophisticatedfastening schemes. One sophisticated scheme is termed “snug/angle”. Thisscheme snugs a bolt or fastener to a value, possibly 20% of finaltorque, then continues rotating the bolt or fastener a prescribed anglebefore stopping. By allowing “lost motion” while the angle encoder 43measures rotational movement, the calibration system, can calibrate apower tool 70 for fastening operations such as “snug/angle”.

FIG. 7 is a cross-sectional schematic drawing of certain components ofthe mechanical tool interface 22 of an embodiment of the calibrationsystem 10. Shown is a top plate 48 in which is provided a femalereceiver or coupling 50 which may be splined and proportioned to couplewith the arresting collar 92 of a power tool 70. The top plate 48 may besecurely fastened to the shippable case 12 and positioned such as shownin FIG. 1. Positioned below the top plate 48 is the strain gauge basedtorque transducer 34 of FIG. 6, here shown in side view. The straingauge based torque transducer 34 may be mounted on bearings 52 such thatthe transducer 34 may be torqued, to some degree, about the axis 44 ofthe square female receiver 40. Shown by dotted lines are arrestingblocks 46 with may be positioned on either side of the torque transducerextension 45 and may be affixed to the bottom of the top plate 48 orotherwise fixed in position to arrest the movement of the distal end ofthe torque transducer extension 45.

FIG. 8 shows the cross-sectional schematic of FIG. 7, but also shows aside view of an output spindle 78 with male square output and a splinedmale reaction collar 92 of a high torque power tool 70, with the powertool 70 positioned to be inserted into the female splined reactioncollar 50 receiver in the top plate 48 and to be simultaneously insertedinto the female square receiver 40 of the torque transducer. Thetransducer is positioned relative to the top plate 48 such that when apower tool 70 is coupled to the mechanical interface the splined malereaction collar 92 of the power tool 70 is fully engaged with the femalesplined reaction collar 50 receiver and the male square output of thepower tool 70 is fully engaged with the female square receiver 40 of thetorque transducer.

FIG. 9 shows the components of FIG. 8 with the high torque power tool 70coupled with the mechanical interface of the calibration system 10 tofacilitate calibration of the power tool 70. The splined male reactioncollar 92 of the power tool 70 is fully engaged with the female splinedreaction collar receiver 50 and the male square output 78 of the powertool 70 is fully engaged with the female square receiver 40 of thetorque transducer 34. When, during calibration operations, the motor ofthe power tool 70 provides rotational power through the gearbox to theoutput spindle 78, a high torque force is applied from the male squareoutput of the spindle 78 to the female square receiver 40 of the torquetransducer 34. Simultaneously the reaction collar 92 of the power tool70 is locked against the splined surfaces of the female splined reactioncollar receiver 50 positioned in the top plate 48 thus inhibiting thepower tool 70 from spinning in reaction to the torque being applied tothe torque transducer 34.

In some embodiments one or more adapter couplings may be provided in thecalibration system to accommodate coupling power tools with varyingsizes of reaction collars and or output spindles to the mechanicalinterface of the calibration system.

Calibration Process

As described previously, the present disclosure relates to a portable,shippable calibration system 10 for power tools, including particularly,high torque power tools. The system may comprise unique electrical andmechanical components and systems in a robust shipping case which iseasily transportable and shippable but also protects the hardware duringshipping. Embodiments of the system can be shipped to virtually anycustomer site needing calibration updates on their power impact tools.For example, in some instances, a supply site, whether local orcentralized, of portable, shippable calibration systems can bemaintained and power tool 70 users desiring calibration of their toolscan simply request shipment and delivery of the portable and shippablecalibration system 10 from the supply site. In such instances the powertool 70 user may pay a fee to the calibration system 10 provider, rentthe calibration systems for her/his own use, or provide othercompensation to the calibration system 10 provider. When the shippablecalibration system 10 is received, the user can, with the automaticfeatures of the present system, conduct her/his own calibration on thepower tools and self-certify the calibration. After the calibration, theshippable calibration system 10 can be shipped back to the local orcentralized supply or shipped directly to another tool owner who hasalso requested shipment and delivery of the calibration system 10. Usingthis system, a power tool 70 user need not purchase her/his owncalibration equipment, but can simply request shipment of the presentcalibration system 10 and use the system's automated controls tocalibrate and certify power tools on site at the tool user's schedulingconvenience. Data communications systems in the present calibrationsystem 10 may confirm to the calibration system 10 provider that thecalibration system 10 was received and used at the requested site aswell as archiving power tool 70 calibration and other data.

During calibration operations, and in overview, the calibration system10 will measure the torque provided by the power tool 70 between thesplined reaction collar female receiver 50 and the square receiver 40 ofthe torque transducer 34 (the “actual torque”) and compare actual torquewith the “target torque” (the torque the power tool 70 is set todeliver). It should be understood that the power tool 70 operates usingsignals from its internal torque transducer 94 as processed by acalibration factor stored, typically in non-volatile memory 88, in thepower tool 70 to drive the motor 84 to achieve and output the “targettorque.” Also, and in overview, the calibration system 10 will, aftercomparing the actual torque with the target torque, then calculate a newand corrected calibration factor for the power tool 70 and upload thatnew and corrected calibration factor to the memory 88 or otherwise tothe electronic control system 90 of the power tool 70. The power tool70, using this new and corrected calibration factor, should then producean actual torque (as may be subsequently checked on the presentcalibration system 10) that corresponds with the target torque to whichthe power tool 70 has been set.

The present system operates without the necessity of using a joint ratesimulator (also known as a run-down adapter) which, in prior artcalibration systems, is used to simulate the fastening process of afastener. In prior art systems, these joint rate simulators aretypically mounted in-line between the tool's drive and the torque testeror sensor and also typically are designed to operate in a clockwisedirection only. During such prior art calibration operations, torque isapplied until the joint simulator 106 is run down and the tool shuts-offand torque readings are analyzed. Then the joint simulator 106 must bebacked off to an appropriate position before a subsequent torquemeasurement is made. Different joint simulators 106 are required fordifferent output spindle 78 sizes and targeted calibration torquelevels. Typical joint simulators 106 may comprise numerous gears, suchas planetary gears, to gear up the simulator and also comprise a brakefor a heightened brake effect during calibration testing. The presentsystem eliminates the need for the gearing and brake of the jointsimulator 106 as well as the joint simulator 106 itself.

The present calibration system 10 may be used to provide a certificateof calibration that accords with the standards of the National Instituteof Standards and Technology (NIST). Such an NIST qualified calibrationcertificate can be generated and uploaded for each power tool 70calibrated.

In other words, rather than a calibration system looking to the entirespin-down of a joint simulator 106 (as prior art systems have done),with the present system full power is applied by the power tool 70, thecontrol unit runs the power tool 70 until it reaches the torque to whichit is set (as measured by the power tool transducer 94 associated withthe output spindle), then a comparison is made between the torque towhich the power tool 70 is set to apply (the targeted torque) and thetorque measured by the calibration system 10 (the actual torque). If anydifferences between the targeted torque and the actual torque aredetected, the calibration system 10 calculates a corrected factor (ornew factor) that is communicated to the memory unit that corrects anydrift or other inaccuracy that is shown by the actual torque compared tothe target torque. Next, the calibration can be repeated to see if thetool (using the newly uploaded corrected factor) will produce an actualtorque that equals or is acceptably close to the target torque.

FIG. 10 shows an overview of the use of the present calibration systemsin calibrating power tools at geographically dispersed locations. At 150one or more portable calibration systems according to the presentdisclosure are trued and calibrated by a system provider, typically at asystem provider supply or calibration site. Calibration of the systemsmay be accomplished by known techniques to ensure that the calibrationsystem(s) themselves are accurately calibrated in preparation forshipment to and use by power tool 70 owners in calibrating their ownpower tools. Further, at 150 data archives stored on the calibrationsystem 10, including power tool 70 firmware and software updates, may beupdated. Also, calibration system 10 firmware and software may beupdated. At 152 shipment of one or more calibration systems 10 may berequested by a tool owner or other entity. At 154 one or morecalibration systems 10 are shipped, such as by common carrier or othersystem, from a calibration system 10 supply site to a locationidentified by the tool owner. At 156 the one or more calibration systems10 are received at the tool owner's designated or identified receivingsite or sites. At step 158 one or more power tools 10 are calibratedusing the calibration system 10 of the present disclosure at a locationchosen by the tool owner or other entity. Such calibration may becarried out by operators without a high level of calibration andcertification training inasmuch as the calibration system 10 of thepresent disclosure may be largely self-contained, calibrationinstructions are provided to the operators by the calibration system 10,and calibration procedures are automatically carried out by thecalibration system 10 based on the data the system detects from eachpower tool 70 during the system's data communications with the powertool 70. At the conclusion of a calibration, data regarding the specificpower tool 70, the location and date of the calibration, and an NISTqualified certificate of calibration can be uploaded into data archives.After calibration of the intended power tools is completed, the one ormore calibration systems (10) may be shipped and returned 160 to thesystem supplier or forwarded to another tool owner site. Such shipmentmay be carried out by common carrier or other shipment methods.

FIGS. 11A-11E show an exemplary process for carrying out calibration ofa power tool 70 using the system of the present disclosure. This processmay be implemented by a power tool owner or other entity after receivingone or more calibration systems 10 such as at step 156 of FIG. 10. Atstep 1000, if not already done, the durable shipping case 12 may beopened and the user interface 16, mechanical interface 22 and otherports presented to the operator. At 1100 the calibration system 10 maybe powered on. The calibration system 10 operating system and centralprocessor 18 may boot up (if not already operating) and datacommunication with the components of the calibration system 10 may beopened. At 1200 local and/or cloud data communication channels may beopened by the calibration system 10. Operator input may be used toidentify or log in to appropriate local data communication systems (suchas WIFI or Ethernet) and/or to identify or log in to appropriate dataarchives. Such data archives may comprise archival records for the powertools to be calibrated and may comprise local or cloud based archivesprovided by the tool owner or hosted by third parties, including by thesupplier of the portable calibration systems. At 1300 the GPS systems 28may be activated, the geolocation of the calibration system 10identified, and that geolocation communicated to the central processor18 or system software for use by the calibration system 10. At 1400 datacommunications with a particular power tool 70 to be calibrated may beestablished. This may be accomplished, typically, by connecting thecalibration system 10 and the power tool 70 by USB cable 38, althoughcables using other protocols may be used. Additionally, wirelesscommunications such as Bluetooth or other protocols may be used tocommunicate between the power tool 70 and the calibration system 10.With data communications established between the power tool 70 and thecalibration system 10, the calibration system 10 may download from thepower tool 70 a “birth certificate” or other data identifying theparticulars of the tool being calibrated. The power tool 70 identity mayalso be identified by reading a bar code on the power tool 70 using abar code reader (not shown) supplied with the calibration system 10.With this bar code supplied identity, the calibration system, using itsown data files or by accessing local or cloud-based files can retrieveall necessary data for calibration of the power tool 70. Further, thecalibration system 10 can perform a check of the power tool 70 with dataor records available locally or on the cloud to see if any firmware orsoftware updates are recommended for the power tool 70. The firmware orsoftware updates can be downloaded via the communications systems of thecalibration system 10 and be uploaded to the power tool 70 or beuploaded to the power tool 70 directly from data archives in thecalibration system 10 itself

At 1500 the power tool 70 may be coupled to the mechanical interface 22of the calibration system 10 such as is shown in FIG. 9. Additionally at1500 a trigger actuator 39 controlled by the central controller 18 maybe fixed to the power tool 70 so that, under control from the centralcontroller 18, the trigger actuator 39 can activate the trigger 74 ofthe power tool 70, thus supplying electrical energy to the motor 70 andproviding torque output from the output spindle 78 to the square femalereceiver 40 of the mechanical interface 22 of the calibration system 10.At 1600 the target torque value is downloaded from the power tool 70 tothe calibration system 10. This step 1600 may also be accomplished at1400 when data communications between the power tool 70 and thecalibration system 10 are established. At 1800 it is confirmed that theoutput signals of the calibration system 10 torque transducer 34 arebeing monitored. With communications established between the power tool70 and the calibration system 10, the target torque downloaded from thepower tool 70 to the calibration system 10, the power tool 70 coupled tothe mechanical interface 22 of the calibration system 10 andconfirmation of this coupling confirmed, and the output signals of thecalibration system 10 torque transducer 34 being monitored, thecalibration system 10 is ready for the actual calibration to occur.

At 1900 the central controller 18 activates the trigger actuator 39.With the trigger 74 actuated the motor 84 is powered on and torque isoutput from the output spindle 78 into the female square receiver 40 ofthe calibration system 10. The power tool 70 control system 90 continuesto provide electric power from the battery 80 to the motor 84 whilemonitoring signals from the power tool 70 torque transducer 94 measuringtorque from the output spindle 78 until the power tool 70 controllercalculates—based on the power tool 70 torque transducer 94 outputsignals and the calibration factor already in the power tool 70 memory88—that the power tool target torque has been attained. At this point,the power tool control system 90 switches power to the motor 84 off andthe tool rotational torque output ceases. During this step 1900 theoutput signals of the calibration system 10 torque transducer 34 aremonitored and are used by the calibration system 10 central controller18 to calculate the actual torque received at the calibration system 10from the power tool 70. At 2000 the central controller deactivates thetrigger actuator 39 and the trigger 74 is returned to the off position.

At 2100 the output signals from the calibration system 10 torquetransducer 34, if not already processed (such as at 1900) are processedby the central controller 18 and the actual torque output of the powertool 70 to the calibration system 10 is calculated. At 2200 the actualtorque measured is compared to the target torque by the centralcontroller 18. At 2300 is shown the decision step or operation of thecalibration system 10 depending on the difference between the targettorque and the actual torque. If the difference is within acceptablelimits, the process moves to step 2700. If the difference is outsideacceptable limits the process moves to step 2400.

At 2400 the central processor 18 calculates a proposed corrected toolspecific torque calibration factor for the power tool 70 beingcalibrated. The central processor 18 calculation may take into accountvarious particulars of the design and operating software/firmware of thepower tool 70 to determine the appropriate proposed corrected toolspecific torque calibration factor for the particular power tool 70. At2500 the proposed corrected tool specific torque calibration factor isuploaded to the power tool memory 88, which typically may benon-volatile memory. At 2600, the process returns to step 1600 and thecalibration process is repeated using the newly proposed corrected toolspecific torque calibration factor. After this repeated calibrationoperation, at step 2300 again if the difference in target and actualtorque is within acceptable limits, the process proceeds to step 2700.

At 2700, successful tool specific calibration is confirmed and at 2800calibration (and calibration factor) data is updated and/or uploadedinto memory of the power tool 70, which is typically non-volatilememory. The data that can be updated or uploaded includes the newlydetermined calibration factor and other data such as the date andlocation of the calibration, identification information of thecalibration system 10 by which the calibration was conducted. At 2900 acalibration certificate may be issued for the power tool 70 and storedin local and/or cloud based data systems and the full calibrationrecord, or portions thereof, may be uploaded to the power tool 70 memory88, to local data storage (such as a facility computer and data system,to memory drives 30 on the calibration system 10, and to data systems onthe cloud which may be accessed via the internet from any location withthe appropriate authorization such as an ID and password. A calibrationcertificate may also be uploaded to the power tool 70 and stored inpower tool 70 memory 88. Additionally, more complete data, including alldata regarding the calibration of the power tool 70 may be uploaded tolocal and/or cloud based data systems.

Finally, at 3000 with calibration completed, the power tool 70 may beremoved from the mechanical interface 22 and disconnected from any datacommunications cables that may have been connected between the powertool 70 and the calibration system 10.

In certain embodiments, the portable calibration system may be used tocalculate separate calibration factors (for the same tool) at differenttarget torques and such separate calibration factors for differenttarget torques may be stored in the electronic control systems 90 of thetool. In other words, for the same tool the portable calibration systemmay calculate and upload to electronic control systems a calibrationfactor X1 for target torque Y1 of the power tool 70. In a separatecalibration process, the portable calibration system 10 may calculate asecond calibration factor X2 for target torque Y2 of the power tool andupload the second calibration factor X2 to the electronic controlsystems 90 such that when via user interface 91 or other means the powertool 70 is set to a target torque Y2, the power tool will utilizecalibration factor X2 instead of X1. And, alternatively if the tool isset to target torque Y1 it will use calibration factor X1. Any number oftarget torques Yn and calibration factors Xn may be applied, calculatedand uploaded to provide specifically accurate torque values at varyingtarget torques of the power tool.

A series of adapters may also be included in the calibration system 10to facilitate coupling of power tools 10 having different sizes orconfigurations of reaction collars 92 and/or different sizes orconfigurations of output spindles 78 from that shown in FIGS. 7-9 withthe mechanical interface 22 of the calibration system 10.

One example of such an adapter is shown in FIGS. 12A-12C. FIG. 12Arepresents a view of an embodiment of mechanical interface 22 and showsfemale splined receiver or coupling 50 and female square receiver 40 aseach may be sized to mate with particular reaction collars 92 and outputspindles 78 of certain power tools. FIG. 12B shows an embodiment of areaction collar spacer 112 having an outer circumferential surface of ashape and diameter to mate with the female splined surface of coupling50 and also having an inner circumferential surface of a shape anddiameter to mate with a male splined surface of a tool reaction collarthat is of a smaller diameter than the diameter of coupling 92. Shown inFIG. 12C is a tool output adapter 114 which has an outer shape anddiameter to mate with the female square receiver 40 and an inner shapeand diameter to receive the square output spindle of a power tool havinga smaller square output than element 78 sized to mate with female squarereceiver 40. The adapters 112 and 114 may have horizontal dimensions orthicknesses sized to mate with the various elements of mechanical toolinterface 22. Additionally, further adapters of different sizes orinternal shapes may be used to accommodate a variety of tool collar andoutput sizes and shapes.

Further, the calibration system 10 may comprise variations on the torquetransducer 34 shown in FIGS. 6-9. For example, the torque transducer mayalternately comprise a plurality of torque transducer elementsintegrally formed with the female square receiver 40 of the torqueconverter of FIG. 6. This plurality of torque transducer elements mayprovide a cascading set of torque transducers such as illustrated inFIGS. 13A-13C. The plurality of torque transducer elements illustratedin FIGS. 13A-13C show how transducers or load cells can be combined instages to achieve both high resolution at low loads and also be capableof reading high loads without suffering damage. Such cascading torquetransducer systems, incorporated into the portable calibration system10, provides a wide range of torque sensing capability and thus may beused to calibrate a variety of tools, from those outputting a relativelylow torque to those outputting a relatively high torque while stillproviding high torque accuracy through the entire range of cascaded loadcells.

The example of FIGS. 13A-13C is shown as a linear system but the systemof cascading load cells can be applied in a rotary application such asshown in FIGS. 6-8. In FIGS. 13A-13C are shown a cascaded set of loadcells 120, 121, and 122, comprising varying springs—a light spring 123in load cell 120, a medium spring 124 in load cell 121 and a heavyspring 125 in load cell 122—and each spring protected by respectiveoverload supports 126, 127 and 128. Also shown is a force being measured129 and a reaction force or chassis ground 130. Load cell 120 has a lowcapacity rating, load cell 121 has a medium capacity rating and loadcell 122 has a high capacity rating.

Signals from each load cell (120, 121 and 122) are communicated to amicroprocessor (such as central processor 18). Depending on the amountof force being measured 129, signals from individual ones of load cells120, 121 or 122 are analyzed to accurately determine the force beingmeasured 129. The microprocessor uses one load cell reading at a time,depending on the values read from the load cells. The microprocessor isprogrammed with a map (such as shown in FIG. 14) that defines transitionpoints (load values) for determining which load cell reading themicroprocessor is to use to determine the force being measured 129.

Shown in FIG. 13A is the cascading set of load cells with a forceapplied 129 that is appropriate for the operating range of light spring123 of load cell 120—or, in other words, in a condition in which loadcell 120 is active. In this circumstance the microprocessor (such ascentral processor 18) analyzes the reading from active load cell 120 todetermine the force being measured 129.

FIG. 13B shows the cascading set in which a greater force 129 is appliedthan in FIG. 13A and wherein the force 129 is appropriate for or withinthe operating range of medium spring 124. In this circumstance, loadcell 120 is protected from overloading by overload support 126 and loadcell 121 is active. Also in this circumstance the microprocessor (suchas central processor 18) analyzes the reading from active load cell 121to determine the force being measured 129.

FIG. 13C shows the cascading set in which a greater force 129 is appliedthan in FIG. 13B and wherein the force 129 is appropriate for or withinthe operating range of heavy spring 125. In this circumstance, loadcells 120 and 121 are protected from overloading by overload supports126 and 127 and load cell 122 is active. Also in this circumstance themicroprocessor (such as central processor 18) analyzes the reading fromactive load cell 122 to determine the force being measured 129.

FIG. 14 shows an example of a map defining transition points (loadvalues) for the microprocessor's determination of which load cell's 120,121, or 122 signal to use in determining the force being measured 129.FIG. 14 shows a plot of load cell output signal vs applied load (forcebeing measured 129). Shown are output signals for each of load cells120, 121 and 122. At relatively low Applied Load values themicroprocessor will calculate the applied load (129) based on signalsfrom load cell 120 as the plot for output signal of load cell 120 risesto “full scale”. As the output signal for load cell 120 reaches “fullscale,” load cell 120 has reached its rating limit and overload support126 protects load cell 120. At approximately this point in the “AppliedLoad” scale, the microprocessor switches to calculate the applied load(129) based on signals from load cell 121. As the output signal for loadcell 121 reaches “full scale” load cell 121 has reached its rating limitand overload support 127 protects load cell 121 (and load cell 120 hasalready reached its rating limit and is similarly protected by overloadsupport 126). At approximately this point in the “Applied Load” scale,the microprocessor switches to calculate the applied load (129) based onsignals from load cell 122. By such a cascading set of load cells, thecalibration system 10 can safely and accurately measure the torque oftools having a broad range of torques.

Having described aspects of the disclosure in detail, it will beapparent that modifications and variations are possible withoutdeparting from the scope of aspects of the disclosure as defined in theappended claims. As various changes could be made in the aboveconstructions, products, and methods without departing from the scope ofaspects of the disclosure, it is intended that all matter contained inthe above description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

What is claimed is:
 1. A portable high torque power tool torquecalibration system, comprising: a portable shippable container in whichare mounted a mechanical tool interface, a user interface and centralprocessor unit; the mechanical interface couplable to a high torquepower tool to be calibrated and configured such that the mechanicalinterface simultaneously locks the power tool against spinning andreceives torque output from an output spindle of the power tool; themechanical interface further comprising a torque transducer operativelyconnected to the central processor; the central processor configured toprocess signals received from the torque transducer and calculate andupload to the power tool being calibrated a calibration correctionfactor specific to the power tool being calibrated.
 2. The calibrationsystem of claim 1 further comprising: an electronic data physicalconnection port mounted to the calibration system and configured to beconnected via data cable to an electronic data physical connection portof a power tool being calibrated; and wherein the central processor isconfigured to download specific tool identification information from apower tool being calibrated via the electronic data physical connectionport.
 3. The calibration system of claim 2 wherein: the centralprocessor is configured to upload at least one calibration correctionfactor to a power tool being calibrated, such calibration correctionfactor being specific to the particular power tool.
 4. The calibrationsystem of claim 3 wherein: the mechanical interface comprises both afemale reaction collar coupling and a square spindle female couplingjointly mounted to simultaneously couple with a male reaction collar anda male square output spindle of a power tool.
 5. The calibration systemof claim 3 wherein: the central processor is configured to receive atarget torque setting from a power tool being calibrated, to processsignals from the torque transducer and to calculate a calibrationcorrection factor based on the signals and the target torque, and toupload the calculated calibration factor to the power tool.
 6. Thecalibration system of claim 3 wherein: the central processor, based ondata downloaded from the power tool being calibrated, is configured toidentify an appropriate calibration process for the particular powertool being calibrated; and is further configured to activate a triggeractuator coupled to a trigger of the power tool, to identify when thetool control unit determines that the tool has reached its target torqueoutput, to process signals received from the torque transducer todetermine the actual torque received at the mechanical interface fromthe power tool operating at its target torque output, to compare theactual torque with the target torque, to compute a new calibrationcorrection factor for the power tool at [at that target torque output],and to upload the new calibration correction factor to the data memoryunit of the power tool.
 7. The calibration system of claim 5 furthercomprising a top plate to which the female reaction collar coupling ismounted and against which the torque transducer is arrested.
 8. Thecalibration system of claim 7 wherein the female square spindle couplinghas an axis through the center of the coupling and the coupling isconfigured in a spindle receiving body partially rotatable about theaxis of the female square spindle coupling.
 9. The calibration system ofclaim 8 wherein the spindle receiving body is mounted on at least onebearing and is at least partially rotatable about the axis of the femalesquare spindle coupling.
 10. The calibration system of claim 9 whereinthe body further comprises a torque transducer positioned to at leastpartially rotate about the axis of the female square spindle and is alsoarrested against rotation by at least one arresting block mounted to theplate.
 11. The calibration system of claim 10 configured such that apower tool can be coupled to the female reaction collar coupling and thefemale output spindle coupling, the power tool power source activated,the power tool providing a target torque output to the female squarecoupling that is measured by the torque transducer.
 12. A method ofproviding distributed self-certification of high torque power tools bytool operators, the method comprising: providing at a supply site aportable self-contained calibration system comprising a shippabledurable container in which is mounted an automated high torque powertool calibration system; receiving a request from a tool operator at alocation remote from the supply site for shipment of the calibrationsystem; shipping the calibration system to the tool operator at theremote location; receiving the calibration system at the remotelocation; connecting a power tool to be calibrated to the automaticcalibration system; calibrating the power tool using the automatedcalibration system; storing a torque calibration certificate issued bythe calibration system; and returning the calibration system to thesupply site.
 13. The method of claim 13, wherein: the step of connectinga power tool to be calibrated to the automatic calibration systemfurther comprises connecting a data communications cable from thecalibration system to the power tool and coupling the power tool to amechanical interface of the calibration system such that the mechanicalinterface simultaneously locks the power tool against spinning andreceives torque output from an output spindle of the power tool.
 14. Themethod of claim 14, wherein: the step of calibrating the power toolusing the automated calibration system further comprises downloadingtool specific identifying information from the power tool to thecalibration system over the connected data communications cable; thecalibration system determining a recommended calibration protocol forthe specific power tool based in part on the downloaded tool specificidentifying information; the calibration system identifying a targettorque setting of the power tool from data downloaded from the powertool; the calibration system activating a trigger actuator coupled tothe power tool; the power tool motor providing torque to the outputspindle of the power tool until an electronic control system of thepower tool determines that the power tool target torque output has beenachieved; the torque from the power tool output spindle beingtransferred to a calibration system torque transducer; signals from thecalibration system torque transducer being monitored by a centralprocessor during the period of the power tool providing torque output tothe calibration system; the central processor processing the signalsfrom the torque transducer to determine the actual torque outputreceived from the power tool at the calibration system and comparing theactual torque to the power tool target torque; the central processorcalculating a correction factor to be applied by the power tool to bringthe power tool actual torque output into acceptable correlation with thetarget torque of the power tool; the calibration system uploading thecalculated correction factor to the power tool electronic controlsystem; the calibration system uploading a calibration certificateverifying the completed calibration of the power tool.
 15. The method ofclaim 15 wherein the calibration system uploads a calibrationcertificate relating to the power tool to data records accessed via thecloud by way of a cellular data system embodied in the calibrationsystem.
 16. The method of claim 15 wherein the calibration system checksthe power tool firmware and determines if a power tool firmware updateis recommended and, at the option of the tool operator, uploads updatedfirmware to the power tool.
 17. The method of claim 17 wherein thecalibration system accesses data records via the cloud to help determinewhether a firmware update for the power tool is recommended and todownload a recommended firmware update.
 18. The method of claim 15wherein the calibration system performs the calibration using selfcontained battery power without accessing an external power source. 19.A portable high torque power tool torque calibration system, comprising:a portable shippable container in which are mounted a mechanical toolinterface, a user interface and central processor unit; the mechanicalinterface couplable to a high torque power tool to be calibrated andconfigured such that the mechanical interface simultaneously locks thepower tool against spinning and receives torque output from an outputspindle of the power tool; the mechanical interface further comprising atorque transducer operatively connected to the central processor; thecentral processor configured to process signals received from the torquetransducer and calculate and upload to the power tool being calibrated acalibration correction factor specific to the power tool beingcalibrated; and the calibration system configured to automaticallyconduct the calibration of a high torque power tool using only powerfrom a self-contained battery system in the calibration system andwithout the use of an external power supply.